Postgres Size-limit

Hi there.

First things first. I just want to say I've moved from Mysql to Postgres
for alot of reasons. :-)

My questions:
=============

* What is the limit my PostgresDB can grow to? 4gigs, 8gigs?
* What sort of system I'am a looking at running postgres on?

Now here's a really confusing one :-)

* Can just can't decide which OS to use here:

FreeBSD or Linux

Which OS would you guys chose?

Last question
==============

* Where can I find some real good tests done on Postgres which will
indicate:

- How fast Postgres really works
- Postgres and other DB compared
- Database UPTIME
- Speed and complexity of DB